Dilations

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but keeps its shape, defined by a center of dilation and a scale factor.

Front

What is the center of dilation?

Back

The center of dilation is a fixed point in the plane about which all points are expanded or contracted during a dilation.

Front

What is a scale factor in dilation?

Back

The scale factor is a number that describes how much a figure is enlarged or reduced during a dilation.

Front

If the scale factor is greater than 1, what happens to the figure?

Back

The figure is enlarged.

Front

If the scale factor is between 0 and 1, what happens to the figure?

Back

The figure is reduced.

Front

How do you find the coordinates of a dilated point?

Back

Multiply the distance from the center of dilation to the original point by the scale factor and then add the coordinates of the center of dilation.

Front

What are the coordinates of point B' if B(4, 3) is dilated by a scale factor of 3 with the origin as the center?

Back

B' = (12, 9)

Front

What happens to the angles of a figure during dilation?

Back

The angles remain the same during dilation.

Front

What is the effect of dilation on parallel lines?

Back

Dilation preserves the parallelism of lines; if two lines are parallel, their images after dilation will also be parallel.

Front

What is the relationship between the original figure and its dilated image?

Back

The original figure and its dilated image are similar, meaning they have the same shape but different sizes.